introduction
Diabetes mellitus adversely affects several organs in the body. The abnormality in carbohydrate metabolism that leads to persistently high levels of blood glucose and the coexisting high levels of fat in the blood cause considerable damage to tissues and organ systems of the body. Targets of such damage include the eyes, kidneys, heart, peripheral nerves and blood vessels.
How Diabetes Affects the Kidneys
The kidneys initially show increased filtration rates for some time. It appears that the presence of glucose increases the amount of filtrates passing through the functional units of the kidneys (the glomeruli). This increases the amount of protein being filtered across the glomerular membranes. This is followed by the appearance of small amounts of protein in the urine. The filtered protein damages the membranes leading to increasing losses of protein in the urine and more damage to the kidneys. Eventually, large amounts of protein are lost in the urine and kidney function begins to deteriorate. Diabetes is one of the commonest causes of end-stage kidney disease. Irreversible damage of the kidneys leads to endless sessions of dialysis, as the kidneys are no longer able to filter out toxic waste from the blood. This is the usual course of diabetic nephropathy.
Another source of damage on the kidneys is the increased tendency to atherosclerosis in diabetes mellitus. There is an increased level of blood fats with deposits in the walls of the blood vessels. Where this affects the blood supply to the kidneys, the diminished blood flow can also damage the kidneys.
Damaged kidneys release a hormone that raises blood pressure, leading to hypertension and heart disease. The resulting hypertension further damages the kidneys, worsening the picture.
Prevention of Kidney Damage in Diabetes
Rigorous blood sugar control is required to prevent or slow the progression of damage to the kidneys in diabetics. A close collaboration with the health care provider with close monitoring of blood sugar and constant urine evaluations will go a long way to detect early changes and adjust treatment to address such changes. Irreversible kidney damage requires kidney transplant, and, unlike in kidney damage by other causes, diabetes will still be around to affect the transplanted kidney.
